From the picture above, if we peep from the viewfinder and put focus point at point A, then from the point A to infinity will be entered in the field of DOF (depth of field) . But we also get the sharpness that is half the distance from point A to the lens also sharp. Or in other words, from the point B to infinity will be sharp.
At the time of celluloid camera lens we get "zone of focus" by reading the enclosed space of the aperture used. See the pictures below:
If you want to make a landscape photograph with the lens and f16 aperture (smallest aperture), set focus about 6m, the closest foreground focus is about 2.9m. It means from the distance 2.9m to infinity will be sharp focused at f16 aperture.
The main goal of knowing the hyperfocal distance is to get the sharpness wide open from the focal point to the point of infinity in landscape photography. So the point is to find the right focus distance to get the focal plane broadest of foreground to background, because in landscape photography we often include foreground and background in the same photo frame in sharp condition evenly.
Thus, Hyperfocal Distance is a useful feature that is the function of the lens aperture (f stop), distance and focal length.
The use of a narrow aperture (e.g. f11, f16 or f22) is helping this process. This is due to the narrow aperture sharp space tends to expand. However, landscape photography is often even more demanding. Foreground that we use often is no more than 20-30 cm in front of the lens. Besides all the areas in the picture sharpness is very important for landscape photographers, they do not want any area that is not sharp. This requires precise autofocus point selection.
In these cases we use hyperfocal technique. This technique essentially select an object at a certain distance to be the focal point. By selecting an object with a certain distance we "maximize" sharp space available. This technique depends on the type of camera body (i.e. sensor size) that is used, aperture and focal length used.
In these cases we use hyperfocal technique . This technique essentially select an object at a certain distance to be the focal point. By selecting an object with a certain distance we "maximize" sharp space available. This technique depends on the type of body that is used, aperture and focal length used. To calculate you can use DOF Master Calculator . This software is available free of charge either online or on the iPhone and Windows Mobile. And you can make a table according to the device you want to take photography.
In the "DOF Master Calculator" you must first enter the "body type" that you use, "aperture" and "focal length". Once you enter this parameter is then seen in the red box no. 1 appears the number "hyperfocal distance". After that we enter the hyperfocal distance to the "subject distance" so "far limit" in the blue box no. 2 to "infinity". If it has not reached the "infinity" increase slightly to reach "infinity". The number "hyperfocal distance" is the distance obtained where we have to do focusing.
"Near limit" in the blue box no.2 is the shortest distance from the lens is still in the category of sharp. While "far limit" is the furthest distance that is still in the category of sharp. Or "zone of focus" were among the "near limit" and "far limit".
Reference to calculate hyperfocal distance can be found in en.wikipedia.org
Tips:
- Hyperfocal technique is especially needed if we use the foreground within the "extreme" close to the lens. If the distance is far enough away from the lens (i.e. 3-4 meters) the technique is no longer relevant.
- Make a stop down to ensure sharpness. Suppose you use a Canon 50D body, 18mm focal length and aperture f11, resulting from the DOF Master Calculator 1.53m hyperfocal distance and near the limit of 0.76m. To assure sharpness, you set the aperture at f16 (1 step below), so the foreground with a distance 76cm in front of the lens certainly sharp.
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